OS 10.4 - tiger vs leopard vs snow leopard - upgrade advice

newbie here. Hoping to get a bit of advice on my first post - I am thinking of upgrading my OS and I am not sure whether to just stick with what I have (10.4.11), upgrade to leopard, or just wait and upgrade to snow leopard.

I am running a 15" macbook pro, 2Ghz core duo, 2Gb ram, 250Gb HDD, X1600. Shes getting a little old now but still screams along providing I dont have the entire CS4 suite open all at once. I use it primarily for graphics work, as well as photo processing ie RAW-jpeg/tiff etc.

The reason I am looking to upgrade is so a few extra programs that are only on 10.5 (updated rapidweaver for example) plus I like the aesthetics of leopard ie being able to run skins on windows etc. I would like the new OS to make the most of my available memory while running but I'm assuming it will chew more than the current OS. Which is why I'm hesitating to upgrade.

I have heard stories of leopard running slower than tiger on older systems, which Im not too keen on. Ideally I want it running as light as possible so I have more juice for apps. In a nutshell,

will leopard hog a significant amount more cpu and ram than tiger?
or will snow leopard run lighter and faster on my system than leopard?

Or will they both chew it to pieces and leave me running CS4 slow and chunky? In which case I am better off staying with my current 10.4.11.

Since Snow Leopard has not been released, there is no one that can fully answer your question. It should be out within the next month. I'd suggest waiting until it's been released to ask the question, much less get any complete answers.

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